<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>标题1</title>
</head>
<body>
    <!-- 以下是内容 -->
     this is text
     <br/><h1>标题1</h1>
     <br/><h2>标题2</h2>
     <br/><h3>标题3</h3>
     <br/><h4>标题4</h4>
     <br/><h5>标题4</h5>
     <br/><h5>标题4</h5>
     <br/><h6>标题4</h6>
     <!-- 以下是段落标签 -->
     <p>
        内容1
        <br/>内容2
        <br/>内容3
     </p>
</body>
</html>